For a long time now I have wanted to look into building a color picker for Dynamo. Primarily because the previous package I utilized, hasn’t been updated for the latest version of Dynamo. This was of course the great UI++ package from the badmonkeys. (This package is awesome by the way. Adam, please update with Konrad’s code ASAP 
)
After much research and investigation, I stumbled upon this API method in the Revit API.
This was a revelation! Finally I can create a color picker without importing a bunch of Python libraries, (*note: this will only work in Revit 2017, as this is where this method was added.) Even better is, that this supports Revit color output as well.
I can’t wait to see what people use this for, especially with mandrill and dynamo player.
Have fun!
-johnP
